harbor53 ,
wow- I didn't even know that was a medical condition! Thank you.

Rodney,
I would not consider:

6) A decent listening chair
7) Parametric eq
8) Time and freq room correction
9) Pleasant ambient lighting
11) Dedicated clean power lines to my hifi

as tweaks as we are defining them here. Im not so sure what #10 means though,

best regards,
Jerry

Best regards,
Jerry
Main System: 861v6, DSP8000s in corners, DSP7000s Center and Sides, 1-9 humans.